Polishing apparatus

A polishing apparatus for polishing a surface of a workpiece, comprising:

• a turntable having an abrasive cloth at an upper surface thereof;
• a top ring positioned above said turntable for supporting the workpiece to be polished and pressing the workpiece against said abrasive cloth;
• a top ring drive shaft coupled to said top ring;
• a spherical bearing interposed between said top ring and said top ring drive shaft for allowing said top ring to tilt upon changes in the inclination of said upper surface of said turntable;
• at least one first pin mounted on said top ring drive shaft and at least one second pin mounted on said top ring, said first pin and said second pin being held in point contact with each other such that torque from said top ring drive shaft is transmitted to said top ring via said pins;
• and
• damping means provided on at least one of said first pin and said second pin for inhibiting the transmission of vibrations from said top ring drive shaft to said top ring.

A polishing apparatus for polishing a surface of a workpiece, comprising:

• a turntable having an abrasive cloth at an upper surface thereof;
• a top ring positioned above said turntable for supporting the workpiece to be polished and pressing the workpiece against said abrasive cloth;
• a top ring drive shaft coupled to said top ring;
• a stationary member supporting said top ring drive shaft;
• a spherical bearing interposed between said top ring and said top ring drive shaft for allowing said top ring to tilt upon changes in the inclination of said upper surface of said turntable;
• and
• damping means for damping said top ring drive shaft, said damping means being provided between said top ring drive shaft and said stationary member supporting said top ring drive shaft.

A polishing apparatus for polishing a surface of a workpiece, comprising:

• a turntable having an abrasive cloth at an upper surface thereof;
• a top ring positioned above said turntable for supporting the workpiece to be polished and pressing the workpiece against said abrasive cloth;
• a top ring drive shaft coupled to said top ring;
• a spherical bearing interposed between said top ring and said top ring drive shaft for allowing said top ring to tilt upon changes in the inclination of said upper surface of said turntable;
• and
• a top ring holder movably mounted on said top ring drive shaft, a plurality of retaining members extending through said top ring holder and fixed to said top ring, and a plurality of springs between said top ring holder and said retaining members, said springs resiliently urging said top ring holder against said top ring drive shaft to hold said top ring in a predetermined plane with respect to said top ring drive shaft.

A polishing apparatus for polishing a surface of a workpiece, comprising:

• a turntable having an abrasive cloth at an upper surface thereof;
• a top ring positioned above said turntable for supporting the workpiece to be polished and pressing the workpiece against said abrasive cloth;
• a top ring drive shaft coupled to said top ring;
• a plate interposed between said top ring and said top ring drive shaft, said plate having an annular lower projection, at a lower surface thereof, which contacts the upper surface of said top ring, pressure distribution at the lower surface of said top ring being established by the area over which said lower projection contacts said top ring;
• and
• a spherical bearing interposed between said plate and said top ring drive shaft, said spherical bearing comprising spherical seats formed in said plate and in said top ring drive shaft, respectively and a single sphere seated in said seats so as to allow said top ring to tilt upon changes in the inclination of said upper surface of said turntable.